The present invention relates to apparatus for the projection by means of a lance of refractory and other material, particularly in metallurgic plant and specifically, in converters. This process is generally called "gunning".
The known processes for the repair or internal relining of converters consist in the application by various methods of a refractory material to the refractory base of the lining which is part worn or has deteriorated.
This is usually carried out manually without precision which leads to an enormous loss of time and material and makes it at least necessary to incline the converter and then remove the slag.
In Patents BE 849524 (Kurosaki Refractories Ltd.) and U.S. Pat. No. 3,827,633 (H. Koundo and S. Kubo) there is described a mobile apparatus in which a lance is movable in an oscillating sleeve which itself can pivot ultimately on a supporting column. The state of the art can be further illustrated by Patent Nos. DE 2 200 667 ( Donezkig), FR 1,528,137 (Demag), U.S. 3,351,289 (Demaison) and AU 422,354.
It should be noted however that most of the modern processes for maintaining converters require the slag to be retained in the converter which makes it difficult to repair certain parts of the converter, particularly those located between the discharge opening and the slag bath. The apparatuses of the prior art include just this inconvenience of not permitting easy access to all these parts without inclining the converter to such an extent that it is impossible to maintain a substantial pocket for slag in the converter.